Abstract: A passive RFID transponder sensor system includes a sensor assembly having a focused field transponder antenna with a highly magnetically permeable transponder antenna stem, and a reader antenna with an electrical reader coil generating a magnetic field having magnetic flux extending between the reader antenna and a sensor assembly. The electrical transponder coil and the electrical reader coil are coupled by the magnetic field, so that information can be transferred to and from the sensor assembly through the magnetic field by which the electrical transponder coil and the electrical reader coil are coupled.

Abstract: A passive RFID transponder sensor system includes a sensor assembly having a focused field transponder antenna with a highly magnetically permeable transponder antenna stem, and a reader antenna with an electrical reader coil generating a magnetic field having magnetic flux extending between the reader antenna and a sensor assembly. The electrical transponder coil and the electrical reader coil are coupled by the magnetic field, so that information can be transferred to and from the sensor assembly through the magnetic field by which the electrical transponder coil and the electrical reader coil are coupled.

Abstract: A passive RFID transponder sensor system includes a sensor assembly having a focused field transponder antenna with a highly magnetically permeable transponder antenna stem, and a reader antenna with an electrical reader coil generating a magnetic field having magnetic flux extending between the reader antenna and a sensor assembly. The electrical transponder coil and the electrical reader coil are coupled by the magnetic field, so that information can be transferred to and from the sensor assembly through the magnetic field by which the electrical transponder coil and the electrical reader coil are coupled.

Abstract: A passive RFID transponder sensor system includes a sensor assembly having a focused field transponder antenna with a highly magnetically permeable transponder antenna stem, and a reader antenna with an electrical reader coil generating a magnetic field having magnetic flux extending between the reader antenna and a sensor assembly. The electrical transponder coil and the electrical reader coil are coupled by the magnetic field, so that information can be transferred to and from the sensor assembly through the magnetic field by which the electrical transponder coil and the electrical reader coil are coupled.

Abstract: In a digital transducer, the output of a piezoelectric transducer bridge is coupled to the input of a comparator whose output switches between two predetermined states. A series of digital values is generated in response to the state of the comparator output and is fed back to balance the bridge. Stored digital values control the span of the transducer.

Abstract: A pressure transducer of the type employing a pressure-responsive diaphragm (11) with silicon piezoresistive strain gauges epitaxially deposited thereon is provided with integral digital thermal compensation of span shift and zero shift. The strain gauges are connected in a bridge circuit (30), and a differential voltage across the bridge circuit is amplified by an instrumentation amplifier (46). A temperature sensitive resistor (36) is deposited on the pressure-responsive diaphragm. This resistor is connected in a bridge circuit (35) the output of which is connected to an analog-to-digital (A/D) converter (54) which generates a digital number corresponding to the measured temperature of the piezoresistive strain gauges. This digital number is used to address pre-programmed correction data stored in a programmable read only memory (PROM) (53). The numerical correction data from the PROM is converted by a digital-to-analog (D/A) converter (55) to an analog correction signal.